This invention relates to the cleaning of spent anodes from an aluminum processing plant and, more particularly, to a method and apparatus for automatically cleaning the cryolite from such spent anodes.
In the aluminum industry, carbon anodes are used during the production of aluminum. The anodes are lowered into a reduction cell during the process of producing the primary aluminum. Cryolite and alumina are heaped into the cell during the process. Throughout the course of the production of the aluminum, the carbon anode is eroded away until only a stub is left. This stub is constituted of a carbon butt mounted on a vertical rod which joins the butt at two or more iron posts embedded in the carbon. During the course of aluminum production, a coating of cryolite builds up over the carbon butt and the end of the support rod and posts.
Heretofore this covering of cryolite has been removed manually using jackhammers and sledge hammers. The cleaning of each butt has required a considerable amount of man hours and, because of the dust and noise involved, has presented serious health safety problems and environmental problems which have been costly to overcome. Furthermore, the cleaning of the butts is a bottle neck in the overall aluminum production process because, until the rods are cleaned, they cannot be returned to the anode shop for refitting in new carbon anodes.